Light-and moistureproof protection for rolls of light-sensitive photographic material



July 2, 1957 F. A. POMEROY El AL 2,797,804

LIGHT AND MOISTUREPROOF PROTECTION FOR ROLLS OF LIGHT-SENSITIVEPHOTOGRAPHIC MATERIAL Filed Jan. 27, 1955 2 Sheets-Sheet l FREDERICKALPOMEROY ALFRED .G. WALTHER v INVENTOR;

ATTORNEYS July 2, 1957 F. A. POMEROY ET AL 2,797,304

LIGHT AND MOISTUREPROOF PROTECTION FOR ROLLS I OF LIGHT-SENSITIVEPHOTOGRAPHIC' MATERIAL Filed Jan. 2], 1955 2 Sheets-Sheet 2 ALFRED a.WALTHER Y INVENTORS M .Q. 714

ATTORNEYS FREDERICK APOMEROY United States Patent 9 ice LIGHT- ANDMOISTUREPROOF PROTECTION FOR ROLLS F LIGHT-SENSITIVE PHOTOGRAPHICMATERIAL Frederick A. Pomeroy and Alfred G. Walther, Eocheste- N. Y.,assignors to Eastman Kodak Company, Rochester, N. Y., a corporation ofNew Jersey Application January 27, 1955, Serial No. 484,366

1 Claim. (Cl. ass-s9 This invention. relates to the packaging oflight-sensitive photographic material such as light-sensitive paper andlight-sensitive film.

In the past rolls of light-sensitive material have generally beenmounted on hub members having flanges so that the light-sensitivematerial may be wound upon these spools or spool-like members to protectthe edges of the sensitive material against light. It has been customaryto provide leader strips and sometimes trailer strips of lightproofmaterial to protect the ends of the roll of sensitized material againstlight. In some instances the leader strips and trailer strips have beenmade moisture resistant or moistureproof but ordinarily such packageshave not been very satisfactory because moisture and/ or light couldusually enter between the flanges and the end convolutions of thesensitized material and thus become more or less fogged or spoiled bymoisture. Even if the paper fitted snugly between the flanges whenpacked, expansion and contraction sometimes occurs and fogging may occurin use. It has been proposed to package such coils of light-sensitivematerial in packages which pass completely around and enclose the spoolsand coils, and to waterproof such a package either by using waterproofmaterial alone or by spraying with waterproof varnish or the like. Whilethis may greatly improve the package before it is opened, it is noteffective if a limited amount of sensitized material is drawn from aroll and the roll has to be taken out in a light room since thewaterproof package above described must be torn apart to utilize thematerial.

Any type of package embodying spools with metal flanges has adisadvantage in that in shipping or through other causes the flanges maybecome bent, marred, dented or distorted and if this occurs and theflanges are bent inwardly, as is usually the case, the edges of thepaper convolution are marred. If the paper is withdrawn from such areel, the bent flange damages each convolution of the paper as itunwinds from the reel. Since small deformation of the flanges may occurunnoticed, sometimes a considerable amount of damaged material may beused before noticing the defects.

It is an object of this invention to overcome some of thesedifiiculties. One object of our invention is to provide a veryinexpensive, durable package of light-sensitive material which is atleast substantially moistureproof and which offers good lightprotection. Another object of our invention is to provide a package soarranged that if the periphery of the roll of light-sensitive materialis dented or damaged, the damaged portion may be unrolled and theremainder utilized without further damaging the edges of the roll.Another object of our invention is to provide a roll in which eachconvolution of the lightsensitive material is adequately protectedagainst light leak. A still further object of our invention is toprovide a roll of light-sensitive material which can be partially used,removed in daylight and reused with a loss of only a few outerconvolutions of paper which may be light 2,797,804 Fatentecl July 2,1957 struck by light passing through the paper itself. A further objectis to provide a moisture and light seal for the end convolutions of acoil of paper which may expand and contract with the paper and stillremain in lighttight and moisture-tight relation thereto. A stillfurther object of our invention is to provide a roll of light-sensitivematerial which is not readily damaged and other objects will appear fromthe following specification, the novel features being particularlypointed out in the claims at the end thereof.

In the drawings, wherein like reference characters denote like partsthroughout:

Fig. l is a perspective view of a preferred form of our improvedlight-sensitive package;

Fig. 2 is a section taken on line 22 of Fig. 1;

Fig. 3 is an enlarged fragmentary section shown partially in elevationindicating the lightproofing arrangement for the edges of the roll oflight-sensitive material;

Fig. 4 is a similar enlarged section showing a different form ofinvention from that in the preceding figures;

Fig. 5 is a part section, part elevation of a coil of photographicsensitive material which has been damaged;

Fig. 6 is a schematic, top plan view of an unrolled piece of sensitizedmaterial with leader and trailer strips attached;

Fig. 7 is a view of a desirable type of material which may be used toform a seal between the end convolutions and an end covering member forthe coiled sensitized roll of material; and

Fig. 8 is a view of another type of material which may be used for thesame purpose.

In all the views the scale is exaggerated to better illustrate theinvention.

Our invention comprises providing a roll of sensitized material wound ona hub, this material. preferably having the ends of the coil covered. bylight and moistureproof material which is temporarily adhered to thecoils of the ends of the roll. There are a number of materials which aresuitable for this purpose such as, for instance, a laminated wrappingwhich consists of paper, foil anl thermoplastic material. Such materialmay include a pressure-sensitive material which is affected by heat orsolvent so that it may firmly adhere to the ends of the convolutions.This material, if of the heat and pressuresensitive type, may be made inthe form of disks or doughnut-shaped portions which are pressed directlyagainst the ends ofthe rolls. These rolls can then be unwound and thepaper will peel away from the adhesive contact with the paper disks andthe roll may be removed in daylight, fogging only the outer fewconvolutions of paper since the remainder of the end convolutions of theroll will be adequately protected from light and moisture by theadhering laminated disks. The expansion and/or contraction of the paperwill not destroy the seal between the disks and the end convolutionssince the two are adhered up to the time of use.

More specifically, as indicated in Fig. 1, a. suitable package maycomprise a roll of material I mounted between two cover members or disks2 of light and moistureproof material which are caused to adhere to theend convolutions of the material 1. The inside of the coil may besupported by a known type of support, such as a cup-shaped member 3, twoof these being provided, one at each end. These may have the usualflanges 4 (or the flanges may be omitted) and openings 5 by which theyare supported in the photographing machines. If desired, the sensitizedstrip 6 may, as shown in Fig. 6, have a light and moistureproof leaderstrip 7 attached, as by a paster 8, and a similar paster 9 may be usedfor a trailer strip 10 although these trailer strips are very seldomused in packages of the preferred type.

The cover members 2 are preferably laminated disks, as indicated in Fig.3, and may include an inner layer 12 which may be a heat andpressure-sensitive material or it may be an adhesive which can besoftened with a solvent or it may be one of the types of materials whichcan be preheated and which will retain its tackiness for some time afterheating so that it may be applied to the end convolutions 13 of thestrip of sensitized material 6, as shown in Fig. 4. When such a packageis used, the sensitized strip 6 may be pulled from the adhesive 12without diificulty, peeling the paper from the adhesive without marringthe edges, but at the same time this tight connection between theadhesive and the ends 13 of the sensitized strip will definitely preventlight from entering between the edges of the paper and the adhesive 12.The disks 2 are preferably quite thin and flexible and, consequently,can readily be pressed into intimate contact with the ends of the coreof sensitive paper. Thus the flexibility is a desirable feature becauseany small inaccuracies in the location of different convolutions can bereadily taken care of when the light and moistureproof adhesive ispressed against the ends of the roll of sensitized material.

With such a package, if the package is dropped or dented in shipment orotherwise, as indicated in Fig. there may be an imperfection where theflexible end protecting member 2 is dented and where a number ofconvolutions of a sensitized material 6 may also be marred, as shown at21. In such a case, by unwinding the marred portions of the paper 6through the convolutions 22 the remainder of the sensitized material maybe readily used without damage since the flexible end covering members2, even though distorted by being mashed inwardly, will straighten outas the sensitized material is unwound to remove the damaged portion. Theend protecting members 2 do not have suflicient rigidity to damage theremaining portion of the sensitized material which can then be readilyused in the normal manner.

It is also noted that if a quantity of the roll of sensitized materialis used, the remaining portion is not materially damaged by removing theroll in a light room since the edges of the sensitized material alwaysremain attached to the adhesive 12 in such a way that they will be heldagainst unwinding or clock springing and, in addition, in such a waythat the ends are perfectly sealed against the entrance of light. Thelittle paper fogged by light passing through the paper itself can bereadily unwound when the roll is again used.

Fig. 7 shows one of the preferred types of material which may be usedfor the end protecting cover members 2. Thus an outer sheet of paper maybe laminated to a layer such as polyethylene 31 and this layer in turnmay be laminated to a layer of foil 32. This layer 32 includes on theopposite side a second layer such as polyethylene 33, which under heatand pressure will adhere to each of the convolutions of sensitizedmaterial 6 when pressed thereagainst.

Fig. 8 shows another example of a laminated protective sheet which mayconsist of several laminations and which includes a substantially waterand lightproof layer to which there is a layer of adhesive 41 of thetype which becomes soft and tacky under heat and which will remain tackyfor a sufficient time for it to be placed in position on the ends of theconvolutions of sensitized material 6. This has the advantage that whendealing with sensitized material, the heat can be so controlled that itwill not desensitize the emulsion as may occur if too much heat is usedwith an ordinary heat and pressure type of adhesive. A typical exampleof an adhesive composition suitable for this type of sealing isdescribed in U. S. Patent 2,462,029, Nashua Gummed and Coated PaperCompany, granted February 15, 1949. The laminated material may be drawnover a heater 42 which may include a conductor 43 and plug 44 all asdiagrammatically shown in Fig. 8.

There are still other types of suitable materials which are light-tightand moistureproof and which have a layer which becomes adhesive upon theapplication of a solvent. Since some solvents do not damage a sensitiveemulsion, such materials are quite suitable for use. A typical exampleof a suitable adhesive is cellulose acetate butyrate containing 38%butyryl groups dissolved in a solvent or thinner of 48% toluene, 24%acetone, 20% denatured ethyl alcohol, 8% #1 naphtha. No plasticizer isrequired and solvent level is not critical.

In this specification and in the claims where sensitized strip materialis referred to, it is to be understood that it covers a sensitized layeron any suitable flexible base such as paper or film which can readily berolled into a coil for shipment and use. It is, however, particularlyadapted for use in a coil of sensitized paper used in photographiccopying machines, particularly where the width of the coil may be ofconsiderable dimensions, such as from one to four or five feet wide,because in such instances the package is quite a heavy one and there isno possibility of some of the layers slipping laterally relative toothers. However, the dimensions are unimportant since this can also besuccessfully used in comparatively narrow widths of film and papersensitized strips.

It may be noted from Fig. 4 that the sensitized material 6 may be woundon a wooden or plastic core 50 which has no flanges corresponding to theflanges 4 of the cupshaped members of Fig. 1. Such cores are quitesatisfactory and the protective disks 2a may readily be used on thistype of package, as indicated in Fig. 4. If desired, the bottom portion12b of the adhesive layer 12 may be turned under so as to adhere to thecore 50 but this is not necessary as the layer of adhesive 12 only needsto come down against the edge of the hub 50 to form a satisfactorylight-tight and a relatively moistureproof joint. If an amount of thesensitized material 6 has been drawn off the reel as shown in Fig. 4,the upper portion of the material 12a may be torn off or folded over theouter convolution left on the roll if it has to be removed in daylight.Even if it is torn off, the light will only penetrate a few of the outerconvolutions so that a material amount of the sensitized material willremain in good condition for future use.

While we have described a preferred embodiment of our invention which iswell adapted for use on existing machines utilizing sensitized materialand an embodiment which will form a quite eflicient light-tight andmoistureproof package, it is obvious that various changes will suggestthemselves to those skilled in the art. We consider as within the scopeof our invention all such forms as come within the scope of the appendedclaim.

We claim:

A package including a coil of strip material having a light-sensitivecoating thereon comprising a supporting hub on which the convolutions ofstrip material are wound with an edge of the strip material lying inconvolutions of gradually increasing size, a cover for the edgeconvolutions of the strip material including a flexible member opaque tolight affecting the light-sensitive surface of the strip material and anadhesive and moistureproof layer between and contacting both theflexible member and the edge convolutions and causing adherence therebetween to prevent the passage of light and moisture therebetween, saidconvolutions being strippable from the adhesive and moistureproof layeras the strip material is unwound from the supporting hub.

Freydberg June 5, 1923 Feuerstein Oct. 22, 1935

